In order to facilitate user fetching and carrying, the general drink containers for takeout beverage are mainly made of paper or plastics and have an opening sealed by a sealing film or a cup lid to prevent the beverage from spilling during carrying or inadvertent toppling. However, the cup with sealed opening generally is not desirable to hold hot beverage. One of the concerns is that the sealing material tends to generate toxic material when heated and create safety issue. Hence the opening-sealed cups and material thereof mostly are used to hold cold beverage.
For general hot drink, a cover lid is commonly employed, especially for hot coffee brewed onsite, as the aroma of the coffee must be generated through boiling water. Because its temperature is usually higher than the general hot drink, it is not suitable to seal the cup opening through a sealing film. Hence the cup opening generally is sealed by a specially made cup lid. For instance, U.S. Pat. No. 6,929,143 discloses a “Plastic drink-through cup lid with fold-back tab”. Its cup lid has a protrusive structure to be pushed for lifting to reveal the cup opening to facilitate user drinking.
The protrusive structure is integrally formed with the cup lid, and the connecting position between the protrusive structure and cup lid has to be severed through a cutter, but still maintains connection between them without fully cut off. When in use, a user has to push the protrusive structure to break off the connection and separate the cup lid. Such a cup lid structure has disadvantages, notably:                1. The connection between the protrusive structure and cup lid is severed via a cutter, but not fully cut off. User has to apply a substantial force to break off the connection between the protrusive structure and cup lid. It cannot fully meet use requirement.        2. Since the cup lid is incorporated with a cup to contain liquid of a higher temperature, the cup lid has to be perforated through an extra process to avoid the problem of thermal pressure and facilitate heat dissipation. There are still rooms for improvement in terms of heat dissipation and air permeability efficacy.        